Field of Invention
The present invention relates to a method for determining a gesture and a gesture detecting apparatus; particularly, it relates to such method and apparatus for determining a gesture according to a variation of a velocity.
Description of Related Art
Generally, for a touch panel, if a user desires to repeatedly expand (zoom-in) the size of the information presented on a displayed page, he or she simply contacts the touch surface with the thumb and the forefinger and repeats an action to expand the distance between the thumb and the forefinger (i.e., the pinch-out action). While repeating the pinch-out action, the user needs to close the thumb and the forefinger back to start a next pinch-out action. Because only the pinch-out action touches the touch surface while the closing action does not touch the touch surface, the repeated pinch-out actions will not be misjudged for a touch panel.
Nevertheless, if the same function is to be performed by optically detecting a gesture of the user by an image sensor, the gesture is likely to be misinterpreted. That is, the image sensor will output a command (e.g., a zoom-in command) in response to a pinch-out gesture (e.g., separating the thumb and the forefinger apart from each other), but when the user closes his or her fingers in order to perform a next pinch-out gesture, the image sensor will also output another command (e.g., a zoom-out command), which is undesirable.